initial: ZeroTier-like P2P mesh VPN server with multi-tenant Web UI

internal/handler/context.go

@@ -0,0 +1,23 @@
+package handler
+
+import "github.com/gin-gonic/gin"
+
+func userID(c *gin.Context) uint {
+	id, exists := c.Get("user_id")
+	if !exists {
+		return 0
+	}
+	uid, ok := id.(uint)
+	if !ok {
+		return 0
+	}
+	return uid
+}
+
+func isAdmin(c *gin.Context) bool {
+	role, exists := c.Get("role")
+	if !exists {
+		return false
+	}
+	return role.(string) == "admin"
+}